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Carbon isotopes in mollusk shell carbonates [PDF]
Geo-Marine Letters, 2008 Mollusk shells contain many isotopic clues about calcification physiology and environmental conditions at the time of shell formation. In this review, we use both published and unpublished data to discuss carbon isotopes in both bivalve and gastropod shell carbonates.
David P. Gillikin, Ted A. McConnaughey
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Deuterium Isotope Effect on Carbon Isotope Fractionation in Photosynthesis [PDF]
Science, 1967 Plants grown in D 2 O show a decreased tendency to fractionate carbon-13 during photosynthetic incorporation of carbon dioxide. The isotopic ratio C 13 /C 12 of the tissues of deuterated plants appears to be proportional to the deuterium content of the tissue.
R. A. Uphaus, Joseph J. Katz
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A carbon isotope challenge to the snowball Earth [PDF]
Nature, 2011 The snowball Earth hypothesis postulates that the planet was entirely covered by ice for millions of years in the Neoproterozoic era, in a self-enhanced glaciation caused by the high albedo of the ice-covered planet. In a hard-snowball picture, the subsequent rapid unfreezing resulted from an ultra-greenhouse event attributed to the buildup of volcanic
Pierre Cartigny +8 more
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Carbon Isotope Abundance in Meteoritic Carbonates
Science, 1963The C 13 /C 12 ratio in the carbonate minerals of Orgueil, a carbonaceous chondrite, is 6 percent greater than the ratio in any known terrestrial carbon. The effect may be produced by a chemical isotope fractionation involving processes not common on earth, or it may be the result of ...
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1993
The stable isotopes of carbon occur in relatively constant proportions throughout the global carbon pool, with 98.89% comprising 12C, and 13C making up 1.11%. However, small but significant variations occur in the proportion of the heavy isotope 13C incorporated into organic and inorganic matter. These depend on the extent of discrimination against (or
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The stable isotopes of carbon occur in relatively constant proportions throughout the global carbon pool, with 98.89% comprising 12C, and 13C making up 1.11%. However, small but significant variations occur in the proportion of the heavy isotope 13C incorporated into organic and inorganic matter. These depend on the extent of discrimination against (or
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Lomagundi Carbon Isotope Excursion
2014The Lomagundi carbon isotope excursion (LCIE), sensu stricto (s.s.), refers to highly positive carbon isotope values (on the average +8 ‰, but values as high as +16 ‰ are not uncommon with the highest values observed at +28 ‰) in Paleoproterozoic sedimentary carbonates deposited between ~2.22 and 2.06 Ga (Karhu and Holland 1996; Bekker et al.
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Isomeres and isotopes of carbon
2020The nuclear geometry has been developed by analogy with the fullerene geometry. On the base of this geometric approach, the structure of carbon isomers and isotopes, which can be obtained by means of nuclear synthesis, has been designed. The mechanisms of possible nuclear reaction are discussed. Carbon is an unusual element.
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1983
The 13C + 13C total fusion cross section has been determined in the range 3.26 ≤ Ec.m. ≤ 8.0 MeV using Ge(Li) detector measurements of low-lying transitions in the residual nuclei and a statistical model calculation of excited state populations. Six different residual nuclei have been observed and their production yields are given.
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The 13C + 13C total fusion cross section has been determined in the range 3.26 ≤ Ec.m. ≤ 8.0 MeV using Ge(Li) detector measurements of low-lying transitions in the residual nuclei and a statistical model calculation of excited state populations. Six different residual nuclei have been observed and their production yields are given.
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Raman detector of carbon isotopes
Optical Sensing and Detection VI, 2020We introduce a Raman scattering based detector of carbon isotopes in gaseous mixtures. A solid state 532 nm 5 W CW laser focused into a gaseoussample by a custom-built diffraction-limited objective was used for excitation of Raman signal. Raman signal was collected by an f-matcher with edge filter at excitation wavelength of 532 nm.
Konstantin Grigorenko +4 more
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Carbon isotope effects in carbonate systems
Geochimica et Cosmochimica Acta, 2004Abstract Global carbon cycle models require a complete understanding of the δ13C variability of the Earth’s C reservoirs as well as the C isotope effects in the transfer of the element among them. An assessment of δ13C changes during CO2 loss from degassing magmas requires knowledge of the melt-CO2 carbon isotope fractionation.
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